With the emergence of e-textbooks, along with expectations to integrate technology in instruction, teachers are becoming significant co-designers of the curriculum. Informed selection and sequencing of learning resources requires sensitivity to didactic nuance, and tools to support development and application of such sensitivity. Teachers’ practices are constrained by the aspects of resources that are “searchable,” which are limited using standard search engines, and the selection of tasks is influenced by the engines’ ranking of search results, reflecting their popularity. We are developing and researching a coupled pair of tools to support mathematics teachers in making informed curricular decisions—a tool for tagging learning resources with prescribed categories of didactic metadata and a dashboard for browsing collections of resources according to this tagged metadata. In this article, we investigate affordances of these tools for the professional development of mathematics teachers—both practicing and pre-service teacher candidates. Viewing the dashboard, along with the metadata that it encodes, as a boundary object between the teachers’ and the researchers’ perspectives on curricular design, we show how teachers learned through acts of boundary crossing, conceived as transitions and interactions between the two communities’ curricular discourses. We show how using the dashboard in a task-selection assignment encouraged teachers to reflect on their practice—making explicit the tacit considerations that they apply to curricular decisions and articulating them from the researchers’ perspective. We also describe the emergence of “hybrid” search strategies, integrating multiple perspectives to create practices that are both didactically informed and practically relevant for instruction.

中文翻译：

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教导性元数据通知教师选择学习资源：专业发展中的界限

随着电子教科书的出现，以及对将技术集成到教学中的期望，教师正在成为课程的重要联合设计者。知情的学习资源选择和排序要求对教学细微差别的敏感性，以及支持这种敏感性的开发和应用的工具。教师的实践受到“可搜索”资源方面的限制，这些资源使用标准搜索引擎进行了限制，并且任务的选择受引擎对搜索结果的排名的影响，反映了它们的受欢迎程度。我们正在开发和研究一对成对的工具，以支持数学老师做出明智的课程决策-一种工具，该工具使用规定的教学元数据类别标记学习资源，仪表板用于根据该标记的元数据浏览资源集合。在本文中，我们研究了这些工具对数学老师的专业发展的支持能力（包括实践和职前教师候选人）。查看仪表板及其编码的元数据，作为教师和研究人员在课程设计观点之间的边界对象，我们展示了教师如何通过边界交叉的行为来学习，这被认为是两个社区之间的过渡和互动。课程内容。我们展示了如何在任务选择作业中使用仪表板来鼓励教师反思他们的实践-明确他们在课程决策中的默认考虑，并从研究人员的角度进行阐述。我们还描述了“混合”搜索策略的出现，它们融合了多种观点来创建既具有教学指导意义又与教学实践相关的实践。